What a 1/5 rating means
On the comedogenic scale, a 1 sits at the safe end of the scale — clogging is unlikely for most people. That places PEG-100 Stearate in the range most people, including many with acne-prone skin, tolerate well.
One thing the number cannot tell you is concentration. Ingredients are listed in descending order, so PEG-100 Stearate near the end of a label is present in tiny amounts and matters far less than the same ingredient near the top.
About PEG-100 Stearate
It is an emulsifier, the ingredient that keeps a product's oil and water phases from separating. A very common co-emulsifier (usually paired with glyceryl stearate) that is low-risk at 1/5, though a fatty-acid ester.
On a label it can read as Peg-100 Stearate, Peg 100 Stearate — worth knowing when you scan an ingredient deck.
PEG-100 Stearate in makeup and skincare
It quietly stabilises most cream foundations, lotions, and moisturisers. Its irritancy is rated separately at 0/5, which is low.
If you deal with fungal acne (malassezia folliculitis) rather than ordinary clogged pores, note that PEG-100 Stearate is among the fatty-acid or ester-type ingredients that community sources commonly avoid — a separate concern from its comedogenic score, and one with weaker evidence behind it.
PEG-100 Stearate comedogenic FAQ
Is PEG-100 Stearate comedogenic?
Not usually. PEG-100 Stearate is rated 1/5, which is low risk on the 0–5 comedogenic scale, so it is unlikely to clog pores for most people, including many with acne-prone skin.
What is the comedogenic rating of PEG-100 Stearate?
PEG-100 Stearate has a comedogenic rating of 1/5 (low risk). Of the 190 ingredients in our dataset with a published rating, 132 rate higher than PEG-100 Stearate, 28 rate lower, and 29 others share its 1/5. Among the 22 rated emulsifiers, 18 rate higher and none lower. The figure is drawn from 1 cited source, listed on this page.
Is PEG-100 Stearate pore-clogging?
It is unlikely to be. At 1/5, PEG-100 Stearate sits in the range generally treated as non-comedogenic. Concentration still matters: an ingredient near the top of a label makes up far more of the product than one near the end. Comedogenic ratings come mostly from rabbit-ear assays and small human patch tests of the pure ingredient at high concentration, so they are a screening guide, not a prediction for your skin or a medical claim.